PP Test Prob

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PP Test Prob

by anupam » Thu Sep 07, 2006 7:21 am
if x<0 , then Sq.Root(-x*|x|) is

x or -x ??

Do we always take the square root of 4 as 2 on GMAT or -2 is also a correct choice !!!
This was in one of my PP tests

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by aim-wsc » Mon Sep 11, 2006 1:47 am
both -ve as well as +ve value.

you always take both values in GMAT

whats the problem btw?

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by anupam » Wed Sep 13, 2006 12:05 am
this was the prob.
and it had both the options x as well as -x
however, i came across in the OG that root of a no will always be positive...

so sq root(9) will be 3

and therefore i think, sq root of (-3*-3) will also be 3

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oh ya

by aim-wsc » Wed Sep 13, 2006 6:54 am
all right.

but be careful in DS questions they consider both cases in DS.

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by r4rohini » Thu Sep 21, 2006 1:27 am
:?
Last edited by r4rohini on Thu Sep 21, 2006 1:38 am, edited 1 time in total.

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by r4rohini » Thu Sep 21, 2006 1:37 am
Plzz ignore my previous reply.. dont know how to delete that... :?

See Square root of a no can be +ve or -ve
And Sqaure root of a -ve no is not possible, its undefined

So for this question
if x<0 , then Sq.Root(-x*|x|) is

assume x=-4

Sq.Root(-(-4)*|-4|) = Sq.Root (4*4) = Sq.Root (16 ) = +4 or -4

So the answer to this question is x and -x